Freshwater Data - Page 5

River water quality is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to excessive growth of river algae, which can degrade habitat.

High concentrations of nitrogen in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals, and nitrate-nitrogen can be toxic to humans. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains the model outputs for river water quality indicators as medians for each river segment in New Zealand’s digital river network.

River water quality is valued for many reasons including recreational value.
Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains the model outputs for E.coli concentrations as four different statistics for each river segment in New Zealand’s digital river network.

Freshwater fish are an important component of freshwater ecosystems, have intrinsic biodiversity values and are a valued resource for Māori, recreational and commercial fishers. The presence of fish species can be affected by changes in catchment land cover and land use, in-stream habitat, fish passages (routes for moving up and down waterways), pests, and contaminants.

File contains predicted capture, including upper and lower confidence intervals for 11 fish species, including indices of native fish, exotic fish, and all fish, over the period 1977 ̶ 2015.

"Macroinvertebrates are small animals without backbones that live on and under submerged logs, rocks, and aquatic plants in the stream bed during some period of their life cycle. They play a central role in stream ecosystems by feeding on periphyton (algae or slime), macrophytes (aquatic plants), dead leaves and wood, or on each other. High Macroinvertebrate Community Index (MCI) scores generally indicate better stream health. Macroinvertebrates are good continuous indicators of the health of their stream environment. This is because they are relatively sedentary and long–lived (a year or more) which means they live with any stresses or changes that occur in their location (eg, pollution, habitat removal, floods and droughts). They complement discrete measures like chemical monitoring, which only reflects the condition at the exact time and place of sampling. Such monitoring might miss effects of a short–lived pollutant or an unanticipated type of disturbance.
This dataset relates to the ""River water quality: benthic macroinvertebrates"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

"Fine sediment is the collective term for inorganic particles deposited on the streambed less than 2mm in size. Urban development and agriculture and forestry around waterways can increase the amount of sediment entering river systems. Sedimentation can clog space between pebbles that are used by aquatic insects and fish, alter food sources, and remove sites used for egg laying. Excess sediment can affect the appeal of rivers and streams for recreation.
This dataset relates to the ""Streambed sedimentation"" measure on the Environmental Indicators, Te taiao Aotearoa website.

Field names
NZREACH Stream segment label
SEDO Predicted observed percentage fine sediment cover, i.e. contemporary state
SEDE Predicted expected percentage fine sediment cover, i.e. reference state. "

"Nitrogen is an essential nutrient for plant growth. It occurs naturally, but in agricultural systems more nitrogen is commonly added to soils as fertiliser or from livestock waste. Not all the additional nitrogen can be taken up by plants. Some nitrogen will drain (leach) as nitrate from the soil and can enter waterways, potentially causing ecological harm. The amount of nitrate leaching from the soil varies around the country, as a result of different land uses, climates, and soils.
This dataset relates to the ""Geographic pattern of agricultural nitrate leaching"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

Nitrogen is an essential nutrient for plant growth. It occurs naturally in the environment but is added in agricultural processes (typically as fertiliser) to boost production. Although much of the applied nitrogen is taken up by plants, livestock waste returns a considerable amount to the soil. Nitrate formed from this waste easily drains (leaches) from the soil before plants can absorb it, and it can enter waterways, potentially harming ecosystems.

This dataset relates to the "Trends in nitrogen leaching from agricultural activities" measure on the Environmental Indicators, Te taiao Aotearoa website.

"Small amounts of nitrogen are a natural component of healthy rivers. Nitrogen in rivers can vary due to differences in land use, climate, elevation, and geology. Nitrogen is transferred from land to water and is cycled through different forms, which can have different effects. Moderate concentrations of nitrate can cause weeds and algae to grow too fast. High concentrations of ammoniacal and nitrate nitrogen can be toxic to fish and other aquatic animals.
This dataset relates to the ""Geographic pattern of nitrogen in river water"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

Small amounts of nitrogen are a natural component of healthy rivers. Nitrogen is transferred from land to water and is cycled through different forms, which can have different effects. Moderate concentrations of nitrate can cause weeds and algae to grow too fast. High concentrations of ammoniacal and nitrate nitrogen can be toxic to fish and other aquatic animals.
This dataset relates to the "River water quality trends: nitrogen" measure on the Environmental Indicators, Te taiao Aotearoa website.